Field of the Invention
The present invention relates to a power transmission apparatus for a vehicle utilizing a double clutch. More particularly, the present invention relates to a power transmission apparatus for a vehicle minimizing its length by disposing a synchronizer for the reverse speed on a separate idle shaft.
Description of Related Art
An environmentally-friendly technology of a vehicle is a core technology which controls survival of a future automobile industry, and advanced car makers have focused their energy on the development of an environmentally-friendly vehicle to achieve environmental and fuel efficiency regulations.
An electric vehicle (EV) or a hybrid electric vehicle (HEV) utilizing electrical energy, a double clutch transmission (DCT) simultaneously enhancing efficiency and convenience, etc., may be examples of such future automotive technology.
The double clutch transmission (DCT) includes two clutch devices and a gear train of a basically manual transmission, selectively transmits a torque input from an engine to two input shafts by using the two clutch devices, and outputs a torque shifted by the gear train.
Such a double clutch transmission (DCT) attempts to compactly realize a multi-stage transmission of more than five speeds. The DCT achieves an automated manual transmission (AMT) that removes necessity of a manual shifting of a driver, by controlling two clutches and synchronizing devices by a controller.
In comparison with an automatic transmission using planetary gears, such a DCT shows merits, such as higher efficiency in power delivery, easier modification in revising or adding parts in order to achieve more shift-stages, etc., and thus gathers more spotlight since it can more comfortably conform with fuel consumption regulation and efficiency in achieving more shift-stages
In order to achieve more shift-stages of a DCT, the number of gears and synchronizing devices may be increased, which results in a drawback of increase in length and weight.
In particular, in the case of applying a DCT to a hybrid vehicle, a drive motor should be additionally installed in a space where an engine and the DCT is installed, and thus minimization in length is regarded as an important factor for the DCT to be well adopted to a hybrid vehicle and to comfortably achieve more shift-stages.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.